Utilize newly introduced [1] sparse-checkout option

I am admittedly a little unsure why files in leading directories,
including the root directory, aren't included. I feel like, based on how
I read the docs, that they should be included, but I'm glad that they're
not.

[1] actions/checkout#1369

.github/workflows/examples-branch.yml

@@ -78,7 +78,13 @@ jobs:
           apt-get update
           apt-get install -y --no-install-recommends ca-certificates
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v3.5.3
+        with:
+          sparse-checkout: examples/${{ matrix.example }}
+      - name: Sparse checkout sanity check
+        run: |
+          [ ! -f package.json ]
+          [ ! -f package-lock.json ]
       - name: Cache NPM modules
         uses: actions/cache@v3
         with:
@@ -89,12 +95,6 @@ jobs:
         with:
           path: ~/.cache/Cypress
           key: cypress-examples
-      # In lack of native support, https://github.com/actions/checkout/issues/172.
-      - name: Make checkout sparse
-        run: |
-          shopt -s extglob
-          rm -rf examples/!(${{ matrix.example }})
-          rm -rf !(examples)
       - name: Retrieve dirty build
         uses: actions/download-artifact@v3
         with: